Device for upsetting metal



A. J. MOORE Sept. 30, 1947.

DEVICE FOR UPSETTING METAL 5 Sheets-Sheet 1 Filed Oct. 29, i945 I A. J. MOORE DEVICE FOR UPSETTING METAL Sept. 30, 1947.

Filed Oct. 29, 1945 5 Sheets-Sheet 2 gwu /wto'n A NU/PE W J. M0

Sept. 30, ,1947. A. J. MOORE DEVICE FOR UPSETTING METAL Filed Oct. 29, 1945 5 Sheets-Sheet 5 DRE AND/FEW J. M0

Sept. 30, 1947-. A. J. MOORE 2,428,173

DEVICE FOR UPSETTING METAL Filed Oct. 29, 1945 5 Sheets- Sheet 4 3 m ANDREW L MUG/PE A. J. MOORE DEVICE FOR UPSETTING METAL Sept. 30, 1947.

5 Sheefs-Sheet 5 Filed Oct. 29, 1945 Patented Sept. 30, 1947 T OFFICE DEVICE FOR UPSETTIN G METAL Andrew J. Moore, Washington, D. 0., assignor to Engineering and Research Corporation, Riverdale, Md, a corporation of Maryland Application October 29, 1945, Serial No. 625,142

This application is a continuation in part of my copending application Serial No. 508,077.

This invention relates to the art of metal forming and, more particularly, to the art of upsetting metal by shrinking or stretching it.

In metal working, and particularly in the formation of aircraft and other parts from aluminum and magnesium sheet, it is often necessary to shrink or stretch the metal over all or a part of the area thereof and it is very desirable to do A typical shrinking operation is the curvature of an elongated strip of within its own plane. In other typical shrinking or stretching operations fiat metal sheet is curved out of its normal plane over all or a part of the area thereof, in either simple or compound curvature.

Devices for shrinking metal are now known to the art. These devices comprise a pair of jaws moved toward each other into engagement with the opposite surfaces of a piece of metal to clamp the same therebetween, a second pair of jaws which is operable in the same way to clamp the metal therebetween over an area closely spaced from the area of operation of the first jaws, and some means to move the two pairs of jaws toward each other while maintaining their clamping engagement with the metal. Known metal stretching devices operate in very much the same way, except that the sets of jaws are moved apart after each set has clamped the work piece. This invention is not to be considered as a mere provide a new, improved and radically difierent device for eifecting sheet metal shrinking and stretching.

Another of eration of the deviceor tool... All of these objects, as 'well 'as'others', have been achieved and are provided by the invention described and illustrated in this application. It will be understood, however, that the description and drawings of this application areonly for the purpose of illustrating the invention, and place sheet metal substantially 3 Claims. (01. 78-61) no limitation thereon pended claims.

Referring to the drawings, in which similar reference numerals refer to like parts,

Fig. 1 is a perspective view of an elongated, rectangular piece of metal;

Fig. 2 is a perspective view of the piece of metal of Fig. 1 after shrinking or stretching one or the other edge thereof by means of the present invention;

Fig. 3 is a perspective view of a tool according to this invention, being shown in its normal or undeformed condition;

Fig. 4 is front elevational view of the tool disclosed in Fig. 3;

Fig. 5 is a view which is similar to Fig. 4 but in which the tool is shown in the deformed condition assumed while effecting a, shrinking operation;

Fig. 6 is a view of a pair of tools formed according to this invention and in position to cooperate in shrinking a piece of metal, being shown in their normal or undeforrned condition;

Fig. 7 is a View which is similar to Fig. 6 but in which the two tools are shown in the de formed conditions assumed while effecting a shrinking operation;

Fig. 8 is an enlarged view of part of a shrinker head according to the invention, showing the shape of the working face thereof;

Fig. 9 is an enlargedview of part of the head shown in Fig. -8, illustrating more particularly the shape of the working face thereof;

Fig. 10 is an enlarged view of part of a shrinker head according to the ferred shape of the working :face thereof;

Figs. 11, 12 and 13 are front elevational views of modified forms of tools formed according to this invention;

Figs. 14 and 15 are front elevational views of tools formed according to this invention and modified to cause them to effect a stretching rather than a shrinking operation;

Figs. 16, 17 and 18 are front elevational views of modified forms of the invention;

Figs. 19 and 20 are front and side elevational views of a machine embodying tools, according to this invention, and

Figs. 21 and 22 are side and front elevational views of a hand tool for shrinking sheet metal, formed according to. this invention.

A typical operation device provided by this invention is illustrated in Figs. 1 and 2 and consists in the deformation of the elongated rectangular piece of metal of Fig. 1 in such a way that it becomes curved substantially in its own plane, asillustrated in Fig. 2, without wrinklingor other deformation. This change in form may be effected by shrinking one not imposed by the apinvention showing a preperformed by the tool or longitudinal edge A of the piece without shrinking the opposite edge B. and the required shrinking is effected by the tool provided by this invention, either when operated alone or in cooperation with another tool of the same or different structure. The same result may be achieved, if desired, by stretching the edge B without operating on the edge A. Other typical operations which may be performed by the means provided by this invention are the curvature of a metal piece out of its own plane, in simple or compound curvature and over all or a part of the area thereof. It is to be understood that the invention is generally useful in shrinking or stretching sheet metal and that the examples of the use of the invention which are described in the specification or shown in the drawings herein are for purposes of illustration only.

My invention consists primarily in the provision of a metal shrinking device comprising a unitary metallic block having jaw members formed as parts thereof and converging from spaced parts thereof, the outer surfaces of the free ends of such jaw members being adjacent but normally separated and forming working surfaces disposed laterally between the connections of the jaw members to the body of the device, whereby when such working surfaces are pressed into engagement with a work piece the jaw members will be flexed inwardly and the working surfaces will be forced together, thereby causing the metal to flow together and at the same time preventing wrinkling or the formation of ridges.

A metal upsetting device according to the invention is disclosed in Figs. 3, 4 and 5 of the drawings and comprises a unitary, integral metallic device which is denoted generally by letter C. This device is preferably formed as a block having the general shape of a parallelepiped as this promotes the ease of manufacture but, if desired, the parts outside the dotted lines D-D of Fig. 4 may be omitted or removed. The block C has a lower or working surface 4 which is adapted to be forced into engagement with the work piece E which is to be shrunk or stretched and which work piece insofar as the disclosure and mscussion of Figs. 4 and 5 is concerned, is carried by a rigid support F. A narrow opening 6 extends preferably along the transverse centerline of the working surface and preferably at right angles theerto and extends from the working surface 4 a short way into the body of the head where it joins an enlarged opening 8. Two narrow diverging openings ID, l2 extend from the opening 8 in directions away from the working surface and toward the side walls l4, l6 and terminate respectively in enlarged openings I8, 20 which are respectively disposed adjacent the opposite side walls l4, [6. Each of the narrow openings 6, l0, l2 and each of the openings 8, i8, 20 preferably extends entirely through the head C from the front to the rear thereof although, if desired, one or all of them may extend through the head only far enough to provide the required function. It will be seen that'these openings substantially divide the head into four sections. The first of these, numbered 22, is of triangular shape and lies between the slots Hi, I2, the second part 24 lies between the slot l and the side wall l4, the third part 26 lies between the slot l2 and the side wall l6, and thefourth part 21 overlies all of these parts and is integrally connected to all of them. In the embodiment shown, the part 21 isprovided with openings by means of which the head may be operably attached to a metal upsetting machine. It will be seen that the part 24, which may be referred to as a jaw, is integrally united to the main body part 21 through the section X-X, which lies between opening 18 and side wall [4, and that part 25, which may also be referred to as a jaw, is integrally united to part 21 by section YY which lies between opening 20 and side wall l6. Each of the jaws 24, 26 includes a part of the lower or working surface A which is, as described, divided' in half by the opening 6.

The shape of the working surface of the jaws is of importance in my invention. In general the working surface is convex, with the most extended part thereof being adjacent the opening 6 which lies between the working surfaces of the two jaws. Thus, the most extended part of the working surface of each jaw is spaced inwardly of the connection of the jaw to the head 21, i. e., the most extended part 28 of jaw 24 is spaced laterally inwardly of section X-X and the most extended part 29 of jaw 26 is spaced laterally inwardly of section Y-Y. It will be seen that when the working surface parts 28, 29 are pressed into engagement with a work piece to shrink the same, each jaw member will act as a lever, bending about some point in or adjacent the section X-X or Y-Y, whereby the jaws will move toward each other to the position shown in Fig. 5.

In order to provide best shrinking operation the shape of the working surface of each jaw must be a curve developed about the center or centers of movement of the jaw. I have found that best results are obtained if the working surface of each jaw member approximates the shape of an involute, and such shape is preferred in the formation of the working surfaces of jaws according to my invention and is shown in Fig. 10. The working surface of each jaw may be otherwise described by saying that it is generally arcuate and convex and that the shape thereof is such that the radius of curvature progressively decreases from the central or most extended part thereof, i. e., the part adjacent the central opening 6, outwardly, with the center of curvature remaining in the center-line (3-0: of the head. Such shape, in addition to the lever action of the jaws, causes each jaw surface to remain in contact with the work piece and to have a tendency to push inwardly on the work piece, i. e., toward the other jaw, when the jaws flex inwardly in the shrinking operation. In Fig. 8 of the drawings there is disclosed in enlarged View a shrinker head according to this invention and showing the shape of a typical working surface. Actual measurement of the distances A, B, C, D, E, at points I, 2, 3, 4, 5, respectively, of a typical jaw which, in the head measured, were located at each one-eight /8) inch point from the edge of the central opening 6 outwardly were;

A .0000 B .0001 C .00025 D--. .0009 E 00175 In pract ce I find that working surfaces of the described shape may be developed in various ways. In a preferred way the working surfaces of the two jaws are first ground at right angles to the centerline G-G of the head over a very small lateral distance producing the surface M-l on each jaw. A shim which is only slightly narrower than the opening 6 is then placed adjacent parts of the two jaws perpendicular and described shape. If produced in this way the working surfaces will be smooth curves and this is shown in Fig. 10.

When it is desired to shrink metal by means of the tool disclosed in Figs. 3, 4 and-5 the working surface thereof is rapidly and intermittently forced into engagement with the work ment with the work piece, the their normal separated positions. parent that the ening of edge A without corresponding shortening of edge B. While it is surface of each head and are spaced inwardly of the connection of the respective J'aw to the head.

It is preferred that the circular openings 8, I8, 20 be provided in the heads. These openings not only facilitate the making of the elongated openings but, in addition, the thickness and consequently the strength or rigidity of the sec- It will be understood that either or both of the heads C, H may be so modified.

7 and Y-.Y.' In the device 'of Fig. 12,. a circular opening replaces the triangular openingof;Fig. 11', while in Fig. 13 a rectangular .openingis shown.

Means are provided by the invention for transforming the sheet metal shrinking device hereinbefore described to a sheet metal. stretching. device, such means comprising means for holding the jaws from movement toward each other when the working surface is forced into engagement with a work piece which is to be stretched, whereby the head a ts in the known manner of a peening hammer. In Fig. 14 there is illustrated a head of the type and construction of that of Fig. 12 having a single circular opening therethrough, within which a plug Bil has been inserted, completely filling the opening and preventing movement of the jaws toward each other. It will be obvious that this principle may be applied to any other embodiment of the invention. In Fig. 15 there is illustrated a head of the preferred form disclosed in Figs. 3, 4 and 5, the same having an opening Bl extending therethrough at right angles to the central opening 6 and preferably relatively near the working surface. A headed bolt 62 extends through this opening and has a nut threaded to one end thereof whereby the pressure parts of the head may be drawn together, as shown, causing the head to act as a solid,unitary device when the working surface thereof is brought into engagement with a work piece.

While all forms of the invention hereinbefore described have comprised an integral head, it is contemplated that devices according to the invention may be formed of a plurality of parts. One such device is disclosed in Fig. 16' and comprises the jaws ill, li'which are connected to a crossmember 1:3 by rigid but yieldable strips 16 which correspond to the sections X--X and Y-Y of other embodiments and each of which is connected at one end to an outer side wall of one of the jaws at a point removed from the working surface thereof and at the other end to the connecting member 18. The parts are arranged in the same relation as in other embodiments of the invention and as the function and operation of the parts are the same as those of the corresponding parts of other embodiments they will not be further described.

A machine for upsetting metal by the use of devices according to my invention is disclosed in Figs. 19 and 20 of the drawings and comprises a machine having a fixed upper part 89 within which is mounted a vertically movable member 82 which carries an upper shrinking or stretching head C which in Figs. 19 and 20 is disclosed as constructed in accordance with the preferred embodiment of the invention but which may be formed in any other way within the scope thereof. -Means such as the pulley 8d and eccentric 86 are provided for rapidly and continuously reciprocating the member 82 and the head C in such a manner that the working surface of the head is rapidly and intermittently forced into engagement with the work piece E. The machine also comprises a lower part 88 on which a lower shrinker head 1-1 is mounted which is preferably of the same construction as the upper head C.

"This head may be supported in a fixed position or may be supported on an intermediate member- 90 having an inclined lower end which rests on theinclined upper surface of a wedge member 92 which may be moved laterally byan adjusting screw 94. By this means the intermediate member Stand the lower head H may be ad- 'justed to vary the clearance between the upper andlower heads. Itis believed that the operation of this machine will be apparent and no. iurther'description thereof or of the operation of the heads in shrinking or stretching sheet metal will be given.

As stated hereinbefore, the tool provided by the invention may be used by itself to effect the shrinking or stretching of a piece of sheet metal E which is carried by av rigid support F, and by the. present invention there is provided a hand tool which may be used in this manner. This tool is disclosed in Figs. 21 and 22 and comprises a head H30 which is constructed and operable in the manner taught by the invention and which may take. the form of any embodiment herein described or other embodiment with n the scope of the invention. A handle IE2, or other means, is attached to the head and provides means for manually operating the same in the manner of a hammer, whereby the working surface HM of the head may be rapidly and intermittently brought into forceful contact with the work piece E, which is mounted on a rigid support F, thereby eifecting the shrinking thereof in the described manner. If desired, the head "in may be additionally weighted by a part 196, which is integrally or otherwise joined thereto, preferably on the opposite side of the handle from the working surface.

It will be seen that the shrinking tool or head which is provided by this invention may be manufactured easily and cheaply and may be of unitary construction. Further, this tool may be used by itself or with other tools to effect metal shrinking or stretching. Further, the devices provided by the invention may be adjusted to provide maximum efficiency for all thicknesses of work. While the specification and claims refer in certain places to vertical reciprocation or upand-down movement, or to upper and lower positions, it will be understood that these terms place no limitation on the invention, being merely illustrative of one mode of operation or position of parts, and that devices and parts thereof according to the invention may be so positioned and operated that the shrinking or stretching heads are positioned horizontally on opposite sides of the work piece, or otherwise.

While there are here described and illustrated a number of different embodiments of the invention, other embodiments as well as modifications ofthose disclosed will occur to those skilled in the art. All of these may be made and practiced without departing in any way from the spirit or scope of the invention, for the limits of which reference must be had to the appended claims.

While there are here described and illustrated a number of different embodiments of the invention,'other embodiments as well as modifications of those disclosed will occur to those skilled in the art. All of these may be made and practiced without departing in any way from the spirit or scope of the invention, for the limits of which reference must be had to the appended claims.

l claim:

l. A metal shrinking tool comprising an integral metallic head having jaw members integral therewith, said jaws being connected to the head byspaced sections which are of such area that they may be fiexedto permit the jaw members to movetoward and away from each other, said jaw members having normally spaced, closely adjacent work-engaging surfaces at their. free ends which are spaced laterally inwardly of the connections of the respective jaw members to the head whereby the jaw members move toward each other by fiexure of said connecting sections when the workengaging surfaces are forced into engagement with a work part of the work-engaging surface adjacent the other and J'aw members each including substantially onehalf of the working surface and being integrally work-engaging surfaces move toward each other during the shrinking operation.

ANDREW J. MOORE.

REFERENCES CITED The following references are of record in the file of this patent:

Number UNITED STATES PATENTS Name Date Junkers June 9, 1931 Junkers Aug. 13, 1935 Lawson Dec. 10, 1935 Joyner Aug. 29, 1944 Beard Dec. 12, 1944 

